Bluetooth Speaker System

We had some old computer speakers sitting around that we utilize in the living room for our ipod or computer. Since I'm a lazy bum I got sick of standing up and "thumbs downing" songs on Pandora or changing songs when we are at the table or entertaining so I went the route of making those suckers bluetooth where we can stream through our phone or computers from anywhere in out place.

I got the bluetooth module from Sparkfun and it has a lot of great documentation on it in regards to getting started. I bought the RN-52 breakout board for convenience but you could go cheaper just buying the module. The speakers I have are 2 speakers and a subwoofer so I cut the audio jack off to see what wires I had. Turnout I had the left speaker, right speaker and a common ground among them. These speakers are externally powered so the signal is already amplified. In the case you would be using headphones or low powered speakers there would be no need to amplify the signal.

Prototype of Bluetooth Speakers

I intend on packaging everything on a protoboard and in a project box. I'm going to power it from a 3.3v wall adapter and add an audio jack if I ever change speakers in the future I won't have to hardwire anything. Functionality wise it works great!

Wheatstone Bridge Hydrometer

So I was not making the wheatstone bridge for my health. My intent was to build a hydrometer for home brewing. There are multiple ways of doing this but I wanted to play around with the strain gages. The principle being the buoyancy of a ping pong ball bolted at the end of a beam would vary as a function of a fluids density or Specific Gravity which is the typical measurement when home brewing.

This was my crude build and attempt at utilizing it as such but was not overall pleased with the results, fun idea. I had a few other ideas for making a hydrometer but ditched them because of cost and complexity to replace a simple glass tube.